Variable Width Vegetative Buffers

• 2012 annual report

Problem: Our nation (and world) has an ever increasing demand for nutritious food. However, we cannot forget that there is an equally important demand for clean and safe water. A major issue facing agriculture today is the degradation of water quality caused by nutrient runoff. Bodies of water ranging from the small tributary in your backyard all the way to the Gulf of Mexico are being negatively impacted by mainstream grain and livestock production. This issue is gaining public attention in a time of heightened environmental awareness. Grain producers are near the core of this issue and need to show leadership on finding a solution or face intervention and tough outside regulation. One solution, non-tree vegetative buffers, encourages farmers to plant a vegetated strip of land between his or her productive field and an adjacent natural or manmade waterway. During a rain event, surface water runoff flows downhill from the elevated farm field to the depressed waterway. Along the way it passes through the vegetated strip. Here, the strip physically separates nutrient carrying soil particles from the surface water runoff-keeping nutrients like phosphorus and nitrogen in the field and clean water in the waterway. Typically the vegetative strips are a consistent width as they run between field and stream. The width of the strip is usually determined by best practice recommendations, or even farm machinery working widths. This methodology is certainly more effective at preventing nutrient runoff than having no vegetative strip, but is its efficacy being maximized? Solution: Any given field’s contours direct differing volumes of surface water runoff to different points along that field’s edge. Additionally, depending on the degree of slope, surface water runoff velocities can be different along different points of the field edge, or vegetative strip. This reality can be likened to variable levels of soil fertility within a single field. When farmers apply a flat rate of fertilizer they are putting too little fertilizer in some areas, and too much in others. Variable rate technology has allowed applicators to put the fertilizer where the field needs it most. In many cases fertilizer costs remain the same as with flat rate application, but the effectiveness of the fertilizer is increased and profits are elevated.